The war on plastic tea bags reached national interest last year when gardener Mike Armitage successfully persuaded PG Tips to go green and he’s now calling on other major tea manufacturers to remove plastic from their tea bags with a new national campaign.

But until every tea manufacturer completely cuts their use of plastic, most of the 165 million cups of tea drunk every day in Britain will still pollute the environment with microplastic.

So raise a cuppa to the county’s favourite drink on National Tea Day with this comprehensive list of which tea you can drink guilt-free.

Clipper

Biodegradable: Yes and No

Progress: Clipper’s String and Tag tea bags do not need to be heat sealable and contain no polypropylene, however, the filter paper Clipper uses for the square tea bags contains polypropylene to provide the heat- seal function. The company has already completed two production trials to test alternative solutions and have another planned in April.

PG Tips

Biodegradable: Not yet

Progress: PG Tips announced in February that all teabags will be made with new plant-based material that is 100 per cent renewable and biodegradable. The first run of tea bags made with the new material have already hit the shelves, however, PG Tips’ manufacturer Unilever has said their aim is for all teabags to be made from 100 per cent plant based material by the end of 2018.

Pukka

Biodegradable: Yes (but not the tea bag sachet)

Progress: Pukka use a simple stitch of organic cotton and a unique folding process to avoid using polypropylene to seal the edges of their tea bags. However, each tea bag is individually wrapped in a sachet which is not yet fully recyclable. Pukka have said they are working on a sustainable solution to replace the Polyethylenef lamination in their tea sachets.

Teapigs

Biodegradable: Yes

Progress: Teapigs’ tea temples are made from cornstarch and paper, 100 per cent plastic free and fully biodegradable.

Tetley

Biodegradable: No

Progress: Tetley have said they are running trials to use a new tea bag tissue which is 100 per cent biodegradable and free from synthetic materials.

Twinings

Biodegradable: Yes and no

Progress: Twinings have said their loose leaf and pyramid tea bag ranges contain no plastic and is fully biodegradable, however, there are heat sealed bags within the Twinings range which do contain traces of plastic. The company has said that they are developing and trialling fully biodegradable tea bags.

Typhoo

Biodegradable: Yes and No

Progress: Typhoo has said their string and tag bags do not contain any plastic because they are folded, however, other tea bags within the Typhoo range do. The company has said they are working on plastic free alternatives.

Yorkshire Tea

Biodegradable: No

Progress: Yorkshire Tea has announced it has been looking into a plant-based, fully biodegradable tea bag paper for a number of months. They have already completed a second round of trials on prototype teabags and will start larger production trials soon. A full update is expected in June.

Scottish Blend

Biodegradable: No

Progress: Although mostly made of paper Scottish Blend do contain a small amount of polypropylene according to manufacturer Unilever. Unilever has said they aim to have Scottish Blend tea bags fully biodegradable by the end of the year.

Supermarket own brands

Aldi

Biodegradable: Yes and no

Progress: Aldi’s Specially Selected Infusion tea bags are plastic free but the supermarket has said it is looking into more sustainable options across the rest of its own brand tea range.

Asda

Biodegradable: No

Progress: Asda has said it is working with suppliers to try and remove plastic from their own brand tea bags.

Co-op

Biodegradable: Not yet

Progress: Co-op announced earlier this year that they are teaming up with their tea suppliers, Typhoo and Ahlstrom-Munksj, to create a fully biodegradable paper tea bag for their 99 range. Co-op aims to have the biodegradable tea bags on shelves later this year.

Lidl

Biodegradable: No

Progress: Lidl said the vast majority of the composition of their tea bags is biodegradable as they use just 1 per cent of non-biodegradable polymers in their tea bags. Lidl and their industry partner, WRAP, encourage consumers to include their used tea bags in compost containers as there will only be a small amount of residue left over. However, the supermarket also added that they are exploring fully biodegradable polymers instead.

M&S

Biodegradable: No

Progress: M&S have said their own brand tea bags do contain plastic but it is on their agenda to make them plastic free in the future.

Sainsbury’s

Biodegradable: Yes and No

Progress: Sainsbury’s said both Taste the Difference and bySainsbury’s Fruit & Herbal infusions are compostable and they are reviewing the materials used for their own brand tea bags.

Waitrose

Biodegradable: No

Progress: The supermarket said they are working to eliminate plastic from all their own brand tea bags and aiming to have all their own-label packaging widely recyclable, reusable or home compostable by 2025.

*Both Morrisons and Tesco were contacted yet did not confirm whether their own brand tea bags contain plastic.